Problem: $ { {-5} \times \left[\begin{array}{rrr}{-2} & {2} & {3} \\ {-1} & {-1} & {-1}\end{array}\right] = {?} } $
To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{rrr}{-5}\times{-2} & {-5}\times{2} & {-5}\times{3} \\ {-5}\times{-1} & {-5}\times{-1} & {-5}\times{-1}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{10} & {-10} & {-15} \\ {5} & {5} & {5}\end{array}\right]}$